The present invention relates to an apparatus for automatically dissolving instant powder, particularly milk powder, in hot water and, in particular, for frothing-up
The instant powder to be dissolved is a nutrient or food stuff, particularly a milk powder or a cocoa mixture. Preferably, it should not only be dissolved but, by the inclusion of air, be additionally converted into milk froth. Under the term milk froth, one should understand such foam to be applied onto drinks, which consists of milk and/or includes milky constituents such as for instance the froth of cocoa-containing drinks.
The apparatus for automatically dissolving instant powder, particularly milk powder, is preferably an integral component of a coffee maker but may also be realized as an independent frothing-up device.
A milk froth generating apparatus for the generation of milk froth from milk powder and hot water earlier suggested by the Applicant comprises a rotationally symmetric hot water sprayer head which includes hot water channels downwardly directed and open at the lower ends (DE 10 2006 008 341.5 (U.S. application Ser. No. 11/708,954)). Some of the hot water channels open at the lower ends are disposed close to an outer convex surface of the hot water sprayer head and may be inclined about 2° to 12° relative to the perpendicular in peripheral direction. Contrary thereto, the hot water channels disposed close to the central axis of the hot water sprayer extend in parallel to the central axis. A hot water pressure generator and a water heater of the milk froth generating device earlier suggested may be realized in different ways. The hot water pressure generator and the water heater of a coffee machine may for instance be used in which the milk froth generating apparatus is integrated. The hot water pressure generator may be a water pump. However, it is also possible that the hot water pressure generator and the water heater are integrated within a water boiler according to the vapor pressure principle. In all those cases, the milk froth is being generated in a frothing vessel open on the top into which, in order to prepare milk froth, a portion each of milk powder is introduced. For milk froth generation, the hot water sprayer head is disposed at a certain distance above the milk powder so that the water jets emanating from the hot water sprayer head impinge approximately equally distributed onto the portion of milk powder in order to dissolve it and, under the inclusion of the air carried along by the water jets, to largely convert it to milk froth. The hot water sprayer head is in this case so adjusted that it is disposed above the froth being generated in order to keep free from it. Due to the formation of the hot water channels disposed close to the outer convex surface and inclined about 2° to 12° relative to the perpendicular, it results that the outer hot water jets emanate with a spin in peripheral direction of the hot water sprayer head, i.e. with a circular component, from it and impinge with a spin onto the milk powder which stimulates thorough mixing of the powder with the hot water and almost simultaneous frothing. A disadvantage may be, however, the required portion-wise introduction of the milk powder into the frothing vessel through the upper opening thereof while the opening should preferably be spaced from the hot water sprayer head. That is why the hot water jets, particularly in case of partial clogging, may reach from the open space between the hot water sprayer head and the frothing vessel into the surrounding thereof, what can be disturbing.